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125  structures 6733  species 0  interactions 20462  sequences 108  architectures

Family: Flavin_Reduct (PF01613)

Summary: Flavin reductase like domain

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Flavin reductase like domain Provide feedback

This is a flavin reductase family consisting of enzymes known to be flavin reductases as well as various oxidoreductase and monooxygenase components. VlmR is a flavin reductase that functions in a two-component enzyme system to provide isobutylamine N-hydroxylase with reduced flavin and may be involved in the synthesis of valanimycin [1]. SnaC is a flavin reductase that provides reduced flavin for the oxidation of pristinamycin IIB to pristinamycin IIA as catalysed by SnaA, SnaB heterodimer [2]. This flavin reductase region characterised by enzymes of the family is present in the C-terminus of potential FMN proteins from Synechocystis sp. suggesting it is a flavin reductase domain [1].

Literature references

  1. Blanc V, Lagneaux D, Didier P, Gil P, Lacroix P, Crouzet J; , J Bacteriol 1995;177:5206-5214.: Cloning and analysis of structural genes from Streptomyces pristinaespiralis encoding enzymes involved in the conversion of pristinamycin IIB to pristinamycin IIA (PIIA): PIIA synthase and NADH:riboflavin 5'-phosphate oxidoreductase. PUBMED:7665509 EPMC:7665509

  2. Parry RJ, Li W; , J Biol Chem 1997;272:23303-23311.: An NADPH:FAD oxidoreductase from the valanimycin producer, Streptomyces viridifaciens. Cloning, analysis, and overexpression. PUBMED:9287340 EPMC:9287340

Internal database links

External database links

This tab holds annotation information from the InterPro database.

InterPro entry IPR002563

This domain can be found in NAD(P)H-flavin oxidoreductases (flavin reductases), a class of enzymes capable of producing reduced flavin for bacterial bioluminescence and other biological processes, and various other oxidoreductase and monooxygenase enzymes [ PUBMED:12829278 , PUBMED:15461461 , PUBMED:11017201 ].

This domain consists of a beta-barrel with Greek key topology, and is related to the ferredoxin reductase-like FAD-binding domain. The flavin reductases have a different dimerisation mode than that found in the PNP oxidase-like family, which also carries an FMN-binding domain with a similar topology.

Gene Ontology

The mapping between Pfam and Gene Ontology is provided by InterPro. If you use this data please cite InterPro.

Domain organisation

Below is a listing of the unique domain organisations or architectures in which this domain is found. More...

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Pfam Clan

This family is a member of clan FMN-binding (CL0336), which has the following description:

This includes those related to the ferredoxin reductase-like FAD-binding domain and those that are Pyridoxine 5'-phosphate oxidase (PNP)-like.

The clan contains the following 10 members:

DUF2255 DUF447 F420H2_quin_red Flavin_Reduct FMN_bind_2 Putative_PNPOx Pyrid_ox_like Pyrid_oxidase_2 Pyridox_ox_2 Pyridox_oxase_2


We store a range of different sequence alignments for families. As well as the seed alignment from which the family is built, we provide the full alignment, generated by searching the sequence database (reference proteomes) using the family HMM. We also generate alignments using four representative proteomes (RP) sets and the UniProtKB sequence database. More...

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You can also download a FASTA format file containing the full-length sequences for all sequences in the full alignment.

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This page displays the phylogenetic tree for this family's seed alignment. We use FastTree to calculate neighbour join trees with a local bootstrap based on 100 resamples (shown next to the tree nodes). FastTree calculates approximately-maximum-likelihood phylogenetic trees from our seed alignment.

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Curation and family details

This section shows the detailed information about the Pfam family. You can see the definitions of many of the terms in this section in the glossary and a fuller explanation of the scoring system that we use in the scores section of the help pages.

Curation View help on the curation process

Seed source: Pfam-B_710 (release 4.1)
Previous IDs: none
Type: Domain
Sequence Ontology: SO:0000417
Author: Bashton M , Bateman A
Number in seed: 75
Number in full: 20462
Average length of the domain: 153.30 aa
Average identity of full alignment: 20 %
Average coverage of the sequence by the domain: 69.93 %

HMM information View help on HMM parameters

HMM build commands:
build method: hmmbuild -o /dev/null HMM SEED
search method: hmmsearch -Z 61295632 -E 1000 --cpu 4 HMM pfamseq
Model details:
Parameter Sequence Domain
Gathering cut-off 27.0 27.0
Trusted cut-off 27.0 27.0
Noise cut-off 26.9 26.9
Model length: 155
Family (HMM) version: 21
Download: download the raw HMM for this family

Species distribution

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Archea Archea Eukaryota Eukaryota
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This visualisation provides a simple graphical representation of the distribution of this family across species. You can find the original interactive tree in the adjacent tab. More...

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For those sequences which have a structure in the Protein DataBank, we use the mapping between UniProt, PDB and Pfam coordinate systems from the PDBe group, to allow us to map Pfam domains onto UniProt sequences and three-dimensional protein structures. The table below shows the structures on which the Flavin_Reduct domain has been found. There are 125 instances of this domain found in the PDB. Note that there may be multiple copies of the domain in a single PDB structure, since many structures contain multiple copies of the same protein sequence.

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